- 根目录:
- drivers
- usb
- musb
- musb_cppi41.c
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/sizes.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include "musb_core.h"
#define RNDIS_REG(x) (0x80 + ((x - 1) * 4))
#define EP_MODE_AUTOREQ_NONE 0
#define EP_MODE_AUTOREQ_ALL_NEOP 1
#define EP_MODE_AUTOREQ_ALWAYS 3
#define EP_MODE_DMA_TRANSPARENT 0
#define EP_MODE_DMA_RNDIS 1
#define EP_MODE_DMA_GEN_RNDIS 3
#define USB_CTRL_TX_MODE 0x70
#define USB_CTRL_RX_MODE 0x74
#define USB_CTRL_AUTOREQ 0xd0
#define USB_TDOWN 0xd8
struct cppi41_dma_channel {
struct dma_channel channel;
struct cppi41_dma_controller *controller;
struct musb_hw_ep *hw_ep;
struct dma_chan *dc;
dma_cookie_t cookie;
u8 port_num;
u8 is_tx;
u8 is_allocated;
u8 usb_toggle;
dma_addr_t buf_addr;
u32 total_len;
u32 prog_len;
u32 transferred;
u32 packet_sz;
struct list_head tx_check;
int tx_zlp;
};
#define MUSB_DMA_NUM_CHANNELS 15
struct cppi41_dma_controller {
struct dma_controller controller;
struct cppi41_dma_channel rx_channel[MUSB_DMA_NUM_CHANNELS];
struct cppi41_dma_channel tx_channel[MUSB_DMA_NUM_CHANNELS];
struct musb *musb;
struct hrtimer early_tx;
struct list_head early_tx_list;
u32 rx_mode;
u32 tx_mode;
u32 auto_req;
};
static void save_rx_toggle(struct cppi41_dma_channel *cppi41_channel)
{
u16 csr;
u8 toggle;
if (cppi41_channel->is_tx)
return;
if (!is_host_active(cppi41_channel->controller->musb))
return;
csr = musb_readw(cppi41_channel->hw_ep->regs, MUSB_RXCSR);
toggle = csr & MUSB_RXCSR_H_DATATOGGLE ? 1 : 0;
cppi41_channel->usb_toggle = toggle;
}
static void update_rx_toggle(struct cppi41_dma_channel *cppi41_channel)
{
struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
struct musb *musb = hw_ep->musb;
u16 csr;
u8 toggle;
if (cppi41_channel->is_tx)
return;
if (!is_host_active(musb))
return;
musb_ep_select(musb->mregs, hw_ep->epnum);
csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
toggle = csr & MUSB_RXCSR_H_DATATOGGLE ? 1 : 0;
/*
* AM335x Advisory 1.0.13: Due to internal synchronisation error the
* data toggle may reset from DATA1 to DATA0 during receiving data from
* more than one endpoint.
*/
if (!toggle && toggle == cppi41_channel->usb_toggle) {
csr |= MUSB_RXCSR_H_DATATOGGLE | MUSB_RXCSR_H_WR_DATATOGGLE;
musb_writew(cppi41_channel->hw_ep->regs, MUSB_RXCSR, csr);
dev_dbg(cppi41_channel->controller->musb->controller,
"Restoring DATA1 toggle.\n");
}
cppi41_channel->usb_toggle = toggle;
}
static bool musb_is_tx_fifo_empty(struct musb_hw_ep *hw_ep)
{
u8 epnum = hw_ep->epnum;
struct musb *musb = hw_ep->musb;
void __iomem *epio = musb->endpoints[epnum].regs;
u16 csr;
musb_ep_select(musb->mregs, hw_ep->epnum);
csr = musb_readw(epio, MUSB_TXCSR);
if (csr & MUSB_TXCSR_TXPKTRDY)
return false;
return true;
}
static void cppi41_dma_callback(void *private_data);
static void cppi41_trans_done(struct cppi41_dma_channel *cppi41_channel)
{
struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
struct musb *musb = hw_ep->musb;
void __iomem *epio = hw_ep->regs;
u16 csr;
if (!cppi41_channel->prog_len ||
(cppi41_channel->channel.status == MUSB_DMA_STATUS_FREE)) {
/* done, complete */
cppi41_channel->channel.actual_len =
cppi41_channel->transferred;
cppi41_channel->channel.status = MUSB_DMA_STATUS_FREE;
cppi41_channel->channel.rx_packet_done = true;
/*
* transmit ZLP using PIO mode for transfers which size is
* multiple of EP packet size.
*/
if (cppi41_channel->tx_zlp && (cppi41_channel->transferred %
cppi41_channel->packet_sz) == 0) {
musb_ep_select(musb->mregs, hw_ep->epnum);
csr = MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY;
musb_writew(epio, MUSB_TXCSR, csr);
}
musb_dma_completion(musb, hw_ep->epnum, cppi41_channel->is_tx);
} else {
/* next iteration, reload */
struct dma_chan *dc = cppi41_channel->dc;
struct dma_async_tx_descriptor *dma_desc;
enum dma_transfer_direction direction;
u32 remain_bytes;
cppi41_channel->buf_addr += cppi41_channel->packet_sz;
remain_bytes = cppi41_channel->total_len;
remain_bytes -= cppi41_channel->transferred;
remain_bytes = min(remain_bytes, cppi41_channel->packet_sz);
cppi41_channel->prog_len = remain_bytes;
direction = cppi41_channel->is_tx ? DMA_MEM_TO_DEV
: DMA_DEV_TO_MEM;
dma_desc = dmaengine_prep_slave_single(dc,
cppi41_channel->buf_addr,
remain_bytes,
direction,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (WARN_ON(!dma_desc))
return;
dma_desc->callback = cppi41_dma_callback;
dma_desc->callback_param = &cppi41_channel->channel;
cppi41_channel->cookie = dma_desc->tx_submit(dma_desc);
dma_async_issue_pending(dc);
if (!cppi41_channel->is_tx) {
musb_ep_select(musb->mregs, hw_ep->epnum);
csr = musb_readw(epio, MUSB_RXCSR);
csr |= MUSB_RXCSR_H_REQPKT;
musb_writew(epio, MUSB_RXCSR, csr);
}
}
}
static enum hrtimer_restart cppi41_recheck_tx_req(struct hrtimer *timer)
{
struct cppi41_dma_controller *controller;
struct cppi41_dma_channel *cppi41_channel, *n;
struct musb *musb;
unsigned long flags;
enum hrtimer_restart ret = HRTIMER_NORESTART;
controller = container_of(timer, struct cppi41_dma_controller,
early_tx);
musb = controller->musb;
spin_lock_irqsave(&musb->lock, flags);
list_for_each_entry_safe(cppi41_channel, n, &controller->early_tx_list,
tx_check) {
bool empty;
struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
empty = musb_is_tx_fifo_empty(hw_ep);
if (empty) {
list_del_init(&cppi41_channel->tx_check);
cppi41_trans_done(cppi41_channel);
}
}
if (!list_empty(&controller->early_tx_list) &&
!hrtimer_is_queued(&controller->early_tx)) {
ret = HRTIMER_RESTART;
hrtimer_forward_now(&controller->early_tx,
ktime_set(0, 20 * NSEC_PER_USEC));
}
spin_unlock_irqrestore(&musb->lock, flags);
return ret;
}
static void cppi41_dma_callback(void *private_data)
{
struct dma_channel *channel = private_data;
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
struct cppi41_dma_controller *controller;
struct musb *musb = hw_ep->musb;
unsigned long flags;
struct dma_tx_state txstate;
u32 transferred;
int is_hs = 0;
bool empty;
spin_lock_irqsave(&musb->lock, flags);
dmaengine_tx_status(cppi41_channel->dc, cppi41_channel->cookie,
&txstate);
transferred = cppi41_channel->prog_len - txstate.residue;
cppi41_channel->transferred += transferred;
dev_dbg(musb->controller, "DMA transfer done on hw_ep=%d bytes=%d/%d\n",
hw_ep->epnum, cppi41_channel->transferred,
cppi41_channel->total_len);
update_rx_toggle(cppi41_channel);
if (cppi41_channel->transferred == cppi41_channel->total_len ||
transferred < cppi41_channel->packet_sz)
cppi41_channel->prog_len = 0;
if (cppi41_channel->is_tx)
empty = musb_is_tx_fifo_empty(hw_ep);
if (!cppi41_channel->is_tx || empty) {
cppi41_trans_done(cppi41_channel);
goto out;
}
/*
* On AM335x it has been observed that the TX interrupt fires
* too early that means the TXFIFO is not yet empty but the DMA
* engine says that it is done with the transfer. We don't
* receive a FIFO empty interrupt so the only thing we can do is
* to poll for the bit. On HS it usually takes 2us, on FS around
* 110us - 150us depending on the transfer size.
* We spin on HS (no longer than than 25us and setup a timer on
* FS to check for the bit and complete the transfer.
*/
controller = cppi41_channel->controller;
if (is_host_active(musb)) {
if (musb->port1_status & USB_PORT_STAT_HIGH_SPEED)
is_hs = 1;
} else {
if (musb->g.speed == USB_SPEED_HIGH)
is_hs = 1;
}
if (is_hs) {
unsigned wait = 25;
do {
empty = musb_is_tx_fifo_empty(hw_ep);
if (empty) {
cppi41_trans_done(cppi41_channel);
goto out;
}
wait--;
if (!wait)
break;
cpu_relax();
} while (1);
}
list_add_tail(&cppi41_channel->tx_check,
&controller->early_tx_list);
if (!hrtimer_is_queued(&controller->early_tx)) {
unsigned long usecs = cppi41_channel->total_len / 10;
hrtimer_start_range_ns(&controller->early_tx,
ktime_set(0, usecs * NSEC_PER_USEC),
20 * NSEC_PER_USEC,
HRTIMER_MODE_REL);
}
out:
spin_unlock_irqrestore(&musb->lock, flags);
}
static u32 update_ep_mode(unsigned ep, unsigned mode, u32 old)
{
unsigned shift;
shift = (ep - 1) * 2;
old &= ~(3 << shift);
old |= mode << shift;
return old;
}
static void cppi41_set_dma_mode(struct cppi41_dma_channel *cppi41_channel,
unsigned mode)
{
struct cppi41_dma_controller *controller = cppi41_channel->controller;
u32 port;
u32 new_mode;
u32 old_mode;
if (cppi41_channel->is_tx)
old_mode = controller->tx_mode;
else
old_mode = controller->rx_mode;
port = cppi41_channel->port_num;
new_mode = update_ep_mode(port, mode, old_mode);
if (new_mode == old_mode)
return;
if (cppi41_channel->is_tx) {
controller->tx_mode = new_mode;
musb_writel(controller->musb->ctrl_base, USB_CTRL_TX_MODE,
new_mode);
} else {
controller->rx_mode = new_mode;
musb_writel(controller->musb->ctrl_base, USB_CTRL_RX_MODE,
new_mode);
}
}
static void cppi41_set_autoreq_mode(struct cppi41_dma_channel *cppi41_channel,
unsigned mode)
{
struct cppi41_dma_controller *controller = cppi41_channel->controller;
u32 port;
u32 new_mode;
u32 old_mode;
old_mode = controller->auto_req;
port = cppi41_channel->port_num;
new_mode = update_ep_mode(port, mode, old_mode);
if (new_mode == old_mode)
return;
controller->auto_req = new_mode;
musb_writel(controller->musb->ctrl_base, USB_CTRL_AUTOREQ, new_mode);
}
static bool cppi41_configure_channel(struct dma_channel *channel,
u16 packet_sz, u8 mode,
dma_addr_t dma_addr, u32 len)
{
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
struct dma_chan *dc = cppi41_channel->dc;
struct dma_async_tx_descriptor *dma_desc;
enum dma_transfer_direction direction;
struct musb *musb = cppi41_channel->controller->musb;
unsigned use_gen_rndis = 0;
dev_dbg(musb->controller,
"configure ep%d/%x packet_sz=%d, mode=%d, dma_addr=0x%llx, len=%d is_tx=%d\n",
cppi41_channel->port_num, RNDIS_REG(cppi41_channel->port_num),
packet_sz, mode, (unsigned long long) dma_addr,
len, cppi41_channel->is_tx);
cppi41_channel->buf_addr = dma_addr;
cppi41_channel->total_len = len;
cppi41_channel->transferred = 0;
cppi41_channel->packet_sz = packet_sz;
cppi41_channel->tx_zlp = (cppi41_channel->is_tx && mode) ? 1 : 0;
/*
* Due to AM335x' Advisory 1.0.13 we are not allowed to transfer more
* than max packet size at a time.
*/
if (cppi41_channel->is_tx)
use_gen_rndis = 1;
if (use_gen_rndis) {
/* RNDIS mode */
if (len > packet_sz) {
musb_writel(musb->ctrl_base,
RNDIS_REG(cppi41_channel->port_num), len);
/* gen rndis */
cppi41_set_dma_mode(cppi41_channel,
EP_MODE_DMA_GEN_RNDIS);
/* auto req */
cppi41_set_autoreq_mode(cppi41_channel,
EP_MODE_AUTOREQ_ALL_NEOP);
} else {
musb_writel(musb->ctrl_base,
RNDIS_REG(cppi41_channel->port_num), 0);
cppi41_set_dma_mode(cppi41_channel,
EP_MODE_DMA_TRANSPARENT);
cppi41_set_autoreq_mode(cppi41_channel,
EP_MODE_AUTOREQ_NONE);
}
} else {
/* fallback mode */
cppi41_set_dma_mode(cppi41_channel, EP_MODE_DMA_TRANSPARENT);
cppi41_set_autoreq_mode(cppi41_channel, EP_MODE_AUTOREQ_NONE);
len = min_t(u32, packet_sz, len);
}
cppi41_channel->prog_len = len;
direction = cppi41_channel->is_tx ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
dma_desc = dmaengine_prep_slave_single(dc, dma_addr, len, direction,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!dma_desc)
return false;
dma_desc->callback = cppi41_dma_callback;
dma_desc->callback_param = channel;
cppi41_channel->cookie = dma_desc->tx_submit(dma_desc);
cppi41_channel->channel.rx_packet_done = false;
save_rx_toggle(cppi41_channel);
dma_async_issue_pending(dc);
return true;
}
static struct dma_channel *cppi41_dma_channel_allocate(struct dma_controller *c,
struct musb_hw_ep *hw_ep, u8 is_tx)
{
struct cppi41_dma_controller *controller = container_of(c,
struct cppi41_dma_controller, controller);
struct cppi41_dma_channel *cppi41_channel = NULL;
u8 ch_num = hw_ep->epnum - 1;
if (ch_num >= MUSB_DMA_NUM_CHANNELS)
return NULL;
if (is_tx)
cppi41_channel = &controller->tx_channel[ch_num];
else
cppi41_channel = &controller->rx_channel[ch_num];
if (!cppi41_channel->dc)
return NULL;
if (cppi41_channel->is_allocated)
return NULL;
cppi41_channel->hw_ep = hw_ep;
cppi41_channel->is_allocated = 1;
return &cppi41_channel->channel;
}
static void cppi41_dma_channel_release(struct dma_channel *channel)
{
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
if (cppi41_channel->is_allocated) {
cppi41_channel->is_allocated = 0;
channel->status = MUSB_DMA_STATUS_FREE;
channel->actual_len = 0;
}
}
static int cppi41_dma_channel_program(struct dma_channel *channel,
u16 packet_sz, u8 mode,
dma_addr_t dma_addr, u32 len)
{
int ret;
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
int hb_mult = 0;
BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN ||
channel->status == MUSB_DMA_STATUS_BUSY);
if (is_host_active(cppi41_channel->controller->musb)) {
if (cppi41_channel->is_tx)
hb_mult = cppi41_channel->hw_ep->out_qh->hb_mult;
else
hb_mult = cppi41_channel->hw_ep->in_qh->hb_mult;
}
channel->status = MUSB_DMA_STATUS_BUSY;
channel->actual_len = 0;
if (hb_mult)
packet_sz = hb_mult * (packet_sz & 0x7FF);
ret = cppi41_configure_channel(channel, packet_sz, mode, dma_addr, len);
if (!ret)
channel->status = MUSB_DMA_STATUS_FREE;
return ret;
}
static int cppi41_is_compatible(struct dma_channel *channel, u16 maxpacket,
void *buf, u32 length)
{
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
struct cppi41_dma_controller *controller = cppi41_channel->controller;
struct musb *musb = controller->musb;
if (is_host_active(musb)) {
WARN_ON(1);
return 1;
}
if (cppi41_channel->hw_ep->ep_in.type != USB_ENDPOINT_XFER_BULK)
return 0;
if (cppi41_channel->is_tx)
return 1;
/* AM335x Advisory 1.0.13. No workaround for device RX mode */
return 0;
}
static int cppi41_dma_channel_abort(struct dma_channel *channel)
{
struct cppi41_dma_channel *cppi41_channel = channel->private_data;
struct cppi41_dma_controller *controller = cppi41_channel->controller;
struct musb *musb = controller->musb;
void __iomem *epio = cppi41_channel->hw_ep->regs;
int tdbit;
int ret;
unsigned is_tx;
u16 csr;
is_tx = cppi41_channel->is_tx;
dev_dbg(musb->controller, "abort channel=%d, is_tx=%d\n",
cppi41_channel->port_num, is_tx);
if (cppi41_channel->channel.status == MUSB_DMA_STATUS_FREE)
return 0;
list_del_init(&cppi41_channel->tx_check);
if (is_tx) {
csr = musb_readw(epio, MUSB_TXCSR);
csr &= ~MUSB_TXCSR_DMAENAB;
musb_writew(epio, MUSB_TXCSR, csr);
} else {
cppi41_set_autoreq_mode(cppi41_channel, EP_MODE_AUTOREQ_NONE);
/* delay to drain to cppi dma pipeline for isoch */
udelay(250);
csr = musb_readw(epio, MUSB_RXCSR);
csr &= ~(MUSB_RXCSR_H_REQPKT | MUSB_RXCSR_DMAENAB);
musb_writew(epio, MUSB_RXCSR, csr);
/* wait to drain cppi dma pipe line */
udelay(50);
csr = musb_readw(epio, MUSB_RXCSR);
if (csr & MUSB_RXCSR_RXPKTRDY) {
csr |= MUSB_RXCSR_FLUSHFIFO;
musb_writew(epio, MUSB_RXCSR, csr);
musb_writew(epio, MUSB_RXCSR, csr);
}
}
tdbit = 1 << cppi41_channel->port_num;
if (is_tx)
tdbit <<= 16;
do {
if (is_tx)
musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
ret = dmaengine_terminate_all(cppi41_channel->dc);
} while (ret == -EAGAIN);
if (is_tx) {
musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
csr = musb_readw(epio, MUSB_TXCSR);
if (csr & MUSB_TXCSR_TXPKTRDY) {
csr |= MUSB_TXCSR_FLUSHFIFO;
musb_writew(epio, MUSB_TXCSR, csr);
}
}
cppi41_channel->channel.status = MUSB_DMA_STATUS_FREE;
return 0;
}
static void cppi41_release_all_dma_chans(struct cppi41_dma_controller *ctrl)
{
struct dma_chan *dc;
int i;
for (i = 0; i < MUSB_DMA_NUM_CHANNELS; i++) {
dc = ctrl->tx_channel[i].dc;
if (dc)
dma_release_channel(dc);
dc = ctrl->rx_channel[i].dc;
if (dc)
dma_release_channel(dc);
}
}
static void cppi41_dma_controller_stop(struct cppi41_dma_controller *controller)
{
cppi41_release_all_dma_chans(controller);
}
static int cppi41_dma_controller_start(struct cppi41_dma_controller *controller)
{
struct musb *musb = controller->musb;
struct device *dev = musb->controller;
struct device_node *np = dev->parent->of_node;
struct cppi41_dma_channel *cppi41_channel;
int count;
int i;
int ret;
count = of_property_count_strings(np, "dma-names");
if (count < 0)
return count;
for (i = 0; i < count; i++) {
struct dma_chan *dc;
struct dma_channel *musb_dma;
const char *str;
unsigned is_tx;
unsigned int port;
ret = of_property_read_string_index(np, "dma-names", i, &str);
if (ret)
goto err;
if (strstarts(str, "tx"))
is_tx = 1;
else if (strstarts(str, "rx"))
is_tx = 0;
else {
dev_err(dev, "Wrong dmatype %s\n", str);
goto err;
}
ret = kstrtouint(str + 2, 0, &port);
if (ret)
goto err;
ret = -EINVAL;
if (port > MUSB_DMA_NUM_CHANNELS || !port)
goto err;
if (is_tx)
cppi41_channel = &controller->tx_channel[port - 1];
else
cppi41_channel = &controller->rx_channel[port - 1];
cppi41_channel->controller = controller;
cppi41_channel->port_num = port;
cppi41_channel->is_tx = is_tx;
INIT_LIST_HEAD(&cppi41_channel->tx_check);
musb_dma = &cppi41_channel->channel;
musb_dma->private_data = cppi41_channel;
musb_dma->status = MUSB_DMA_STATUS_FREE;
musb_dma->max_len = SZ_4M;
dc = dma_request_slave_channel(dev->parent, str);
if (!dc) {
dev_err(dev, "Failed to request %s.\n", str);
ret = -EPROBE_DEFER;
goto err;
}
cppi41_channel->dc = dc;
}
return 0;
err:
cppi41_release_all_dma_chans(controller);
return ret;
}
void cppi41_dma_controller_destroy(struct dma_controller *c)
{
struct cppi41_dma_controller *controller = container_of(c,
struct cppi41_dma_controller, controller);
hrtimer_cancel(&controller->early_tx);
cppi41_dma_controller_stop(controller);
kfree(controller);
}
EXPORT_SYMBOL_GPL(cppi41_dma_controller_destroy);
struct dma_controller *
cppi41_dma_controller_create(struct musb *musb, void __iomem *base)
{
struct cppi41_dma_controller *controller;
int ret = 0;
if (!musb->controller->parent->of_node) {
dev_err(musb->controller, "Need DT for the DMA engine.\n");
return NULL;
}
controller = kzalloc(sizeof(*controller), GFP_KERNEL);
if (!controller)
goto kzalloc_fail;
hrtimer_init(&controller->early_tx, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
controller->early_tx.function = cppi41_recheck_tx_req;
INIT_LIST_HEAD(&controller->early_tx_list);
controller->musb = musb;
controller->controller.channel_alloc = cppi41_dma_channel_allocate;
controller->controller.channel_release = cppi41_dma_channel_release;
controller->controller.channel_program = cppi41_dma_channel_program;
controller->controller.channel_abort = cppi41_dma_channel_abort;
controller->controller.is_compatible = cppi41_is_compatible;
ret = cppi41_dma_controller_start(controller);
if (ret)
goto plat_get_fail;
return &controller->controller;
plat_get_fail:
kfree(controller);
kzalloc_fail:
if (ret == -EPROBE_DEFER)
return ERR_PTR(ret);
return NULL;
}
EXPORT_SYMBOL_GPL(cppi41_dma_controller_create);